JPWO2010079743A1 - Lubricant composition and lubricating liquid composition - Google Patents

Abstract

Provided are a lubricant composition and a lubricating liquid composition which exhibit sufficient lubricity even with an extremely small amount of oil, reduce friction and wear, and exhibit high extreme pressure properties, wear resistance and rust prevention properties. Mineral oil-based, synthetic oil-based and / or animal and vegetable oil-based lubricant base oils with 3,4,5-trihydroxybenzoic acid and / or 3,4,5-trihydroxybenzoic acid ester as the basis for the total lubricant composition And a lubricant composition having a semi-solid state at room temperature in which 0.01 to 20% by mass of a thickener or an amide compound is blended in an amount of 1 to 70% by mass based on the total lubricant composition. A lubricating liquid composition obtained by mixing 95 to 15 parts by weight of a volatile solvent with respect to 5 to 85 parts by weight of the product.

Description

  The present invention relates to various bearings, gears, and pistons widely used in various types of industrial machines such as home appliances, OA equipment, precision machines, machine tools, transportation machines such as automobiles, motorcycles, bicycles, and railways, and measuring equipment. The present invention relates to a lubricant composition and a lubricant composition having a semi-solid state used for lubricating various sliding parts such as a cylinder and a drive system.

  In mechanical systems such as industrial machines, transportation machines, and measuring instruments, there are various sliding parts such as various bearings, gears, piston cylinders, and drive systems, and frictional wear is constantly repeated. If lubrication failure occurs in these sliding portions, the lubrication system or a mechanical system including the lubrication system cannot perform a desired function. Therefore, various lubricants are used for the sliding portion according to the use environment and conditions. In general, lubricating oils and greases are widely used, but materials having excellent lubricity are used for the members constituting the sliding parts themselves, or surface treatment that imparts excellent lubricity is used. Various correspondences such as performing are given.

Li grease, Ca grease, which contains lithium (Li) soap, calcium (Ca) soap, or urea as a thickener, among liquid lubricants and semi-solid greases commonly used as lubricants. In some cases, urea grease is mixed with a solid lubricant to improve wear resistance, and has a certain effect.
However, in recent years, the load on the sliding portion has increased due to the reduction in size, speed, and load of the mechanical system, and a lubricant that is more excellent in lubricity such as wear resistance and extreme pressure has been demanded. Furthermore, there is a demand for a lubricant that can ensure sufficient lubricity even with an extremely small amount of oil.
On the other hand, thermoreversible gel lubricants having low friction characteristics as compared with Li grease and urea grease have also been developed (Patent Documents 1 to 3). However, in applications where the lubrication conditions are extremely severe, higher extreme pressure properties, wear resistance, and rust prevention properties are required.

WO2006 / 051671 JP 2008-231293 A JP 2008-239840 A

  The present invention solves the problems of high extreme pressure, wear resistance and rust prevention in a sliding member that is more severe by increasing the speed, increasing the load, and reducing the amount of oil. The problem to be solved is a lubricant composition and a lubricating liquid composition that exhibit sufficient lubricity even with a very small amount of oil, reduce friction and wear, and exhibit high extreme pressure properties, wear resistance and rust prevention properties. It is to provide.

  In order to solve the above-mentioned problems by improving the performance of the lubricant, the present inventors have investigated and studied the characteristics of various organic compounds and their blending ratios. As a result, 3,4,5-trihydroxybenzoic acid or It has been found that by blending the ester with a semi-solid lubricant at room temperature, the lubricity can be greatly improved and high rust prevention can be obtained. The present invention has been found to be particularly suitable for greases and gel lubricants, and further diluting them with a volatile solvent to obtain a quick-drying lubricant. The present invention has been completed based on such findings.

That is, the present invention provides the following lubricant composition and lubricating liquid composition.
(1) Lubricant composition of 3,4,5-trihydroxybenzoic acid and / or 3,4,5-trihydroxybenzoic acid ester to mineral base oil, synthetic oil base and / or animal and vegetable base oil A lubricant composition having a semi-solid form at room temperature, in which 0.01 to 20% by mass based on the total amount of the substance and at least one thickener or amide compound is blended in an amount of 1 to 70% by mass based on the total amount of the lubricant composition.

(2) 3,4,5-trihydroxybenzoate is synthesized from 3,4,5-trihydroxybenzoic acid and a linear or branched alcohol having 3 to 12 carbon atoms. The lubricant composition according to the above (1), which is an alkyl ester of trihydroxybenzoic acid.
(3) The lubricant composition according to the above (1) or (2), wherein the lubricating base oil has a kinematic viscosity at 40 ° C. of 5 to 1000 mm ² / s.
(4) The lubricant composition according to any one of the above (1) to (3), which is gelled at room temperature in which the amide compound is blended.
(5) The lubricant composition according to any one of (1) to (4), wherein the consistency is 70 to 480.
(6) The lubricant composition according to any one of the above (1) to (5), which contains 0.01 to 10% by mass of molybdenum compound as molybdenum (Mo) based on the total amount of the lubricant composition.
(7) The lubricating oil composition according to any one of the above (1) to (6), which contains 0.05 to 5.0% by mass of an oiliness agent based on the total amount of the lubricating oil composition.

(8) A lubricating liquid composition obtained by mixing 95 to 15 parts by weight of a volatile solvent with respect to 5 to 85 parts by weight of the lubricant composition according to the above (1) to (7).
(9) The lubricating liquid composition according to (8), wherein the volatile solvent is a hydrocarbon having 6 to 12 carbon atoms.

  Since the lubricant composition and the lubricating liquid composition of the present invention are blended with 3,4,5-trihydroxybenzoic acid or its ester, the wear is remarkably reduced and the friction coefficient is low and stable. By reducing hematite, which is iron red rust, to hard and strong black rust (magnetite), the rust prevention effect can be remarkably improved. That is, when the surface of the sliding material becomes magnetite, lubricity is greatly improved due to a synergistic effect with the antiwear agent. Conventionally, there are products that use black rust conversion effects such as tannic acid in aqueous solution, but there are no products that are oil-soluble and applicable to oil-based lubricants. Most of the mechanical system lubrication in the world is oil-based, and therefore the lubricant composition and the lubricating liquid composition of the present invention contribute to extending the life of mechanical systems with severe lubrication conditions and have a low and stable coefficient of friction. From the above characteristics, energy savings are achieved, and in addition, it contributes to resource savings due to its high rust prevention properties.

The lubricant composition of the present invention comprises a mineral base oil, synthetic oil base and / or animal and vegetable base oil base oil and 3,4,5-trihydroxybenzoic acid or an ester thereof, a thickener or an amide compound. The semi-solid state is obtained at room temperature by blending the above.
3,4,5-Trihydroxybenzoic acid or its esters are generally low in solubility in base oils, so liquid lubricants can be used only at low concentrations, but by making them semisolid lubricants at room temperature Can be used in a wide range of applications.
Here, “normal temperature” means an ordinary temperature in the room, specifically, a temperature environment of 50 ° C. or less, more generally about −10 to 30 ° C. The semi-solid form is one having a consistency of 70 to 480 measured by the method defined in JIS K2220 “7.

[Lubricant base oil]
In the present invention, as the lubricating base oil, a lubricating base oil such as mineral oil, synthetic oil, animal or vegetable oil can be used. Further, two or more of these lubricating base oils can be mixed and used.
The physical properties of the lubricating base oil are not particularly limited, but those having a kinematic viscosity at 40 ° C. of 5 to 1000 mm ² / s are preferable, those of 10 to 600 mm ² / s are more preferable, and 20 to 500 mm are more preferable. ² / s. The lower the viscosity of the lubricating base oil, the lower the friction.
The viscosity index is preferably 90 or more, more preferably 100 to 250, the pour point is preferably -10 ° C or less, more preferably -15 to -70 ° C, and the flash point is preferably 150 ° C or more. More preferably, the temperature is 200 ° C. or higher.
The lubricating base oil is preferably blended in an amount of 10 to 99 mass%, particularly 40 to 95 mass%, based on the total amount of the lubricant composition.

  Mineral oil-based lubricating base oils can be obtained by subjecting a lubricating oil fraction obtained by atmospheric distillation of crude oil or by vacuum distillation of atmospheric distillation residue, etc., to solvent removal, solvent extraction, hydrocracking, solvent A refined lubricating oil fraction obtained by treatment by appropriately combining lubricating oil refining means such as dewaxing, hydrodewaxing, hydrorefining, sulfuric acid washing and clay treatment can be suitably used. Refined lubricating oil fractions having different properties obtained from a combination of various raw materials and various purification means may be used alone or in combination of two or more. Mineral oil base oils made from a fraction having a relatively high boiling point of petroleum are generally inexpensive and are widely used for various lubricating oils and greases.

  Synthetic oil base oils include poly-α-olefin (PAO), poly-α-olefin oligomers such as ethylene-α-olefin oligomer, alkylbenzene, alkyl naphthene, glycol, ester, ether, silicone oil. , Fluorinated oil and the like can be selected as appropriate. Of these, PAO and esters are preferred. In particular, PAO is excellent in terms of viscosity characteristics, oxidation stability, material compatibility, and cost, and is more preferable. These synthetic oils can be used alone or in combination of two or more as long as the above physical properties are satisfied.

  Poly-α-olefins are chemically inert, have excellent viscosity characteristics, and have a wide range of viscosities, which are preferred in terms of cost. Poly-α-olefin is a polymer obtained by polymerizing olefin oligomers such as 1-decene, 1-dodecene, or 1-tetradecene, and blending these polymers appropriately for viscosity adjustment within the range of polymerization degree 2-10. Is preferred.

  Esters are also commercially available as compounds with various molecular structures, each having unique viscosity characteristics (high viscosity index, low pour point), and a base oil with a high flash point compared to hydrocarbon base oils of the same viscosity. It is. Esters can be obtained by dehydration condensation reaction of alcohols and fatty acids. In the present invention, however, diesters and polyols (particularly neopentyl polyols) of dibasic acids and monohydric alcohols in terms of chemical stability. ) And a monovalent fatty acid, or a complex ester of a polyol, a polybasic acid and a monohydric alcohol (or monohydric fatty acid) can be mentioned as a suitable lubricating base oil.

  Animal and vegetable oil-based lubricating base oils include milk fat, beef tallow, lard (pig tallow), sheep fat, beef leg oil, whale oil coconut oil, bonito oil, herring oil, coconut oil, and soybean oil, rapeseed oil, Sunflower oil, safflower oil, peanut oil, corn oil, cottonseed oil, rice bran oil, kapok oil, sesame oil, olive oil, linseed oil, castor oil, cacao butter, sha fat, palm oil, palm kernel oil, coconut oil, hemp seed oil, Rice oil, tea seed oil and the like are suitable, but not limited to these.

  Usually, these base oils such as mineral oils, synthetic oils and animal and vegetable oils can be appropriately combined and blended at an appropriate ratio so as to satisfy various performances required for each application. At this time, a plurality of lubricating base oils of mineral oil type, synthetic oil type and animal and vegetable oil type may be used.

[3,4,5-trihydroxybenzoic acid]
In the present invention, among 3,4,5-trihydroxybenzoic acid compounds, 3,4,5-trihydroxybenzoic acid or 3,4,5-trihydroxybenzoic acid ester is blended. This 3,4,5-trihydroxybenzoic acid, so-called gallic acid, may be used in the acid state, but an ester is preferable in consideration of solubility in a lubricating base oil. Alkyl esters are particularly suitable. Among alkyl esters of 3,4,5-trihydroxybenzoic acid, methyl ester, ethyl ester, propyl ester, butyl ester, hexyl ester, octyl ester, decyl ester, dodecyl ester, etc. can be used. Alkyl ester of 3,4,5-trihydroxybenzoic acid synthesized with 4,5-trihydroxybenzoic acid and a linear or branched alcohol having 3 to 12 carbon atoms is soluble, extreme pressure, and abrasion resistant In view of effects such as rust prevention, it is particularly preferable. The alkyl group may be linear or branched.
The 3,4,5-trihydroxybenzoic acid and / or the ester of 3,4,5-trihydroxybenzoic acid is blended in an amount of 0.01 to 20% by mass based on the total amount of the lubricant composition. When the content is 0.01% by mass or less, the lubricity and the rust preventive property are not sufficiently improved, and even when blended by 20% by mass or more, the improvement of the lubricity and the rust preventive property cannot be expected. The blending amount is preferably 0.1 to 10% by mass, particularly preferably 0.1 to 3% by mass.

[Thickener]
A thickener is used to make the lubricant semi-solid at room temperature. There is no restriction | limiting in particular as a thickener used by this invention, Both a soap type and a non-soap type can be used. As this thickener, those having a dropping point of grease of 230 ° C. or higher are preferable. When the dropping point is 230 ° C. or higher, it is possible to suppress lubrication problems such as softening at high temperature, leakage associated therewith, and seizure.

  As the soap system, a metal soap obtained by saponifying a carboxylic acid or an ester thereof with a metal hydroxide such as an alkali metal or an alkaline earth metal is preferable. Examples of metals in this case include sodium, calcium, lithium, and aluminum. Examples of carboxylic acids include crude fatty acids obtained by hydrolyzing fats and oils to remove glycerin, monocarboxylic acids such as stearic acid, and 12-hydroxystearic acid. Suitable are monobasic carboxylic acids such as dihydroxy acids such as azelaic acid, and aromatic carboxylic acids such as terephthalic acid, salicylic acid and benzoic acid. These may be used individually by 1 type and may be used in combination of 2 or more type. Specifically, lithium-based lithium soap using 12-hydroxystearic acid is particularly preferable.

Non-soap thickeners include urea compounds (polyureas) and fluorine resins in organic systems, and benton and silica gel in inorganic systems.
As a urea compound, arbitrary things can be used from the urea compounds conventionally used as a urea-type thickener. This urea compound includes a diurea compound, a triurea compound, a tetraurea compound, a urea / urethane compound, and the like, and may be appropriately selected and used depending on the purpose. A urea compound is excellent in both heat resistance and water resistance, and particularly excellent in stability at high temperatures, and therefore is suitably used in a high temperature location.

  This thickener is blended to impart consistency, and if the blending amount is too small, the desired consistency cannot be obtained, while if the blending amount is too large, the lubricity is lowered. This blending amount is not particularly limited as long as a semi-solid lubricant can be obtained at room temperature, and is 1 to 70% by mass, preferably 10 to 30% by mass, based on the total amount of the lubricant composition. Preferably, 10 to 20% by mass is appropriately selected and blended, but it is preferable that the consistency is 70 to 480.

[Amide compound]
In the present invention, a lubricant composition that is semi-solid (gel) at room temperature can be obtained by changing to the thickener or by blending an amide compound with the thickener. The amide compound acts as a gelling agent corresponding to the above thickener, and becomes a liquid when the melting point of the gelling agent is exceeded, and becomes a semi-solid (gel-like) below the melting point. ) To give thermoreversible temperature characteristics.

The amide compound used in the present invention is a fatty acid amide compound having one or more amide groups (—NH—CO—), a monoamide having one amide group represented by the following formula (1), and the formula (2 ) And (3) bisamides having two amide groups can be preferably used.

In the above formula (1), R ¹ and R ² are each independently a saturated or unsaturated chain hydrocarbon group having 5 to 25 carbon atoms, and R ² may be hydrogen.

In the above formulas (2) and (3), R ³ , R ⁴ , R ⁵ and R ⁶ are each independently a saturated or unsaturated chain hydrocarbon group having 5 to 25 carbon atoms, and A ¹ And A ² is a C 1-10 divalent hydrocarbon group selected from an alkylene group having 1 to 10 carbon atoms, a phenylene group, or an alkylphenylene group having 7 to 10 carbon atoms. In the case of an alkylphenylene group, it may be a divalent hydrocarbon group in which two or more of a phenylene group and an alkyl group and / or an alkylene group are bonded.

The monoamide compound is represented by the above formula (1), but a part of hydrogen constituting R ¹ and R ² may be substituted with a hydroxyl group. Specific examples of such monoamide compounds include saturated fatty acid amides such as lauric acid amide, palmitic acid amide, stearic acid amide, behenic acid amide, and hydroxystearic acid amide, and unsaturated fatty acids such as oleic acid amide and erucic acid amide. Examples thereof include amides, and substituted amides with saturated or unsaturated long-chain fatty acids and long-chain amines such as stearyl stearamide, oleyl oleate, oleyl stearate, stearyl oleamide, and the like.

Among these monoamide compounds, R ¹ and R ^{2 in} the formula (1) are each independently an amide compound of a saturated chain hydrocarbon group having 12 to 20 carbon atoms and / or at least one of R ¹ and R ² Is preferably an amide compound of an unsaturated chain hydrocarbon group having 12 to 20 carbon atoms, and more preferably a mixture of both amide compounds. Furthermore, a monoamide compound in which the unsaturated chain hydrocarbon group is an oleyl group having an unsaturated bond having 18 carbon atoms is preferred. Specifically, oleic acid amide, oleyl oleic acid amide, oleyl stearic acid amide, and stearyl oleic acid amide are preferable, and a thin film is formed and held on the sliding part to ensure effective thin film retention to eliminate seizure trouble. To do.

The bisamide compound is a compound represented by the above formula (2) or (3) in the form of a diamine acid amide or a diacid acid amide. In the formulas (2) and (3), in the hydrocarbon groups represented by R ³ , R ⁴ , R ⁵ and R ⁶ , and A ¹ and A ² , some hydrogens are substituted with hydroxyl groups (—OH). May be.
Specific examples of the amide compound represented by the formula (2) include ethylene bisstearic acid amide, ethylene bisisostearic acid amide, ethylene bisoleic acid amide, methylene bislauric acid amide, hexamethylene bisoleic acid amide, hexamethylene Examples thereof include bishydroxystearic acid amide and m-xylylene bisstearic acid amide. Specific examples of the amide compound represented by the formula (3) include N, N′-distearyl sebacic acid amide.

Among these bisamide compounds, as in the case of the monoamide compound, R ³ and R ⁴ in formula (2) and R ⁵ and R ^{6 in} formula (3) are each independently a saturated chain carbonization having 12 to 20 carbon atoms. Preferably, the amide compound of a hydrogen group and / or at least one of R ³ and R ⁴ and R ⁵ and R ⁶ is an amide compound of an unsaturated chain hydrocarbon group having 12 to 20 carbon atoms, both amide compounds The mixture of is more preferable. Further, a bisamide compound in which the unsaturated chain hydrocarbon group is an oleyl group having an unsaturated bond having 18 carbon atoms is preferable for ensuring thin film retention. Examples of such compounds include ethylene bisoleic acid amide and hexamethylene bisoleic acid amide.

  In order to prevent seizure in a severe lubrication environment at sliding parts where only a small amount of oil can be used due to mechanical system design restrictions, the oil adheres firmly to the sliding surface. Must hold the oil film. For this purpose, an oil agent having adhesiveness is required, but in the present invention, if the hydrocarbon group of the amide compound that is a gelling agent is an unsaturated chain, the adhesiveness is increased. When the adhesion increases, it can be applied to the sliding surface in a thin film, and it becomes difficult to cause an oil film breakage even in a severe lubrication environment, and the lubrication performance is improved. The unsaturated chain hydrocarbon group is preferably a bisamide compound which is an alkenyl group having an unsaturated bond having 12 to 20 carbon atoms, particularly an oleyl group having an unsaturated bond having 18 carbon atoms.

  An amide compound is mix | blended so that 1-70 mass% may be contained on the basis of the lubricant composition which is a semi-solid form at the normal temperature of completion. If the amount of the amide compound is less than 1% by mass, a gel-like composition cannot be formed at room temperature. On the other hand, if it exceeds 90% by mass, it becomes too hard and difficult to handle. Absent. More preferable amounts are 1 to 50% by mass and 5 to 30% by mass.

[Molybdenum compound]
In addition, by combining the above-mentioned lubricant composition with a molybdenum compound such as molybdenum-containing organic molybdenum compound and molybdenum disulfide, the friction coefficient is further reduced by the synergistic effect with the gallic acid compound, thereby improving the lubricating performance. Can be improved. As the organic molybdenum compound, molybdenum dithiocarbamate (MoDTC), molybdenum dithiophosphate (MoDTP), or the like is preferable. In addition, molybdenum disulfide generally used as a solid lubricant can be used, and can be stably dispersed in a semi-solid lubricant. The amount of the molybdenum compound is preferably 0.1 to 10% by mass, more preferably 0.1 to 3.0% by mass, based on the total amount of the lubricant composition as molybdenum atoms (Mo). is there.
[Oil-based agent]
A synergistic effect with the gallic acid compound can also be obtained by using an oily agent in combination with the lubricant composition. As this oily agent, higher fatty acids such as oleic acid and stearic acid, alcohols such as oleyl alcohol, glycerin monooleate, and glycerin monooleyl ether, esters, ethers, amines, and sulfurized fats and oils are preferable. The blending amount of these oily agents is preferably 0.05 to 5.0% by mass, more preferably 0.1 to 3.0% by mass, based on the total amount of the lubricant composition as a compound. .

[Volatile solvent]
In the present invention, when 95 to 15 parts by weight of a volatile solvent is further mixed with 5 to 85 parts by weight of the above-described lubricant composition, quick drying and high permeability, and after drying, a thin film is formed on the material surface. A special lubricating liquid composition can be obtained.
In this case, the volatile solvent has a boiling point in the range of 40 to 200 ° C., and is any one or more of hydrocarbon, aromatic, alcohol, ether, and ketone that are liquid at room temperature, or these are appropriately selected. It can be used by mixing. These volatile solvents have a boiling point of 40 to 200 ° C., preferably 60 to 150 ° C., more preferably 80 to 150 ° C. If the boiling point is 40 ° C. or less, volatilization is excessive at room temperature, making it difficult to use practically. If it is 200 ° C. or higher, it takes time for drying and vacuum drying, resulting in an increase in cost. In particular, hydrocarbons such as benzine, petroleum ether, kerosene and n-paraffin, aromatics such as toluene and xylene, alcohols such as ethanol, propyl alcohol, butanol and octanol, ethers such as dimethyl ether and diethyl ether These general-purpose solvents are preferable in terms of cost. Among these, hydrocarbons having 6 to 12 carbon atoms are desirable in that the load on the working environment of volatile components is small.

  The lubricating liquid composition of the present invention diluted with a volatile solvent can be uniformly immersed in a processing material such as metal, resin, or ceramic, applied to the surface using a brush, brush, or the like, sprayed, or The lubricating liquid composition is brought into contact with the entire surface of the material by spraying it in a liquid state. Subsequently, in order to remove only a volatile component from the composition, the composition is left to stand, blown, or heated as necessary to dry. As a result, it is possible to form a film on the lubricated sliding parts of the mechanical system, prevent frictional wear after being incorporated into the system, and operate the mechanical system smoothly. In addition, it is possible to prevent rust on the metal storage material, the material being transported by sea, and the metal surface of the machine, and keep a new state.

[Other additives]
In the lubricant composition and the lubricating liquid composition of the present invention, alkaline earth metal-based cleaners that have been conventionally used for grease, gel-like lubricants, lubricating oils and the like within a range that does not impair the object of the present invention. Add additives such as additives, friction modifiers, antiwear agents, extreme pressure agents, detergent dispersants, antioxidants, rust inhibitors, metal deactivators, antifoaming agents, etc. to improve performance. be able to.

  The alkaline earth metal detergent contains an alkaline earth metal such as magnesium, calcium, barium, and examples thereof include alkaline earth metal sulfonate, alkaline earth metal phenate, alkaline earth metal salicylate, and the like. . Friction modifiers include acidic phosphate esters, phosphate ester amine salts, phosphite ester amine salts, antiwear agents such as phosphate esters and zinc dialkyldithiophosphates, extreme pressure agents such as sulfurized olefins and sulfurized fats and oils As the dispersant, polyalkenyl succinimide, polyalkenyl succinic acid ester, each boric acid modified product, and the like can be used. Antioxidants such as amine and phenolic antioxidants, metal deactivators such as benzotriazole, rust preventives such as alkenyl succinic acid esters or partial esters, and antifoaming agents such as silicone compounds And ester antifoaming agents.

  The use of the lubricant composition and the lubricant composition of the present invention can be preferably used depending on the field in which the grease is used and the field in which the rust inhibitor and the surface treatment agent are used. It can also be used under non-special equipment, parts and conditions. In particular, the lubricating liquid composition of the present invention diluted with a solvent can penetrate into a narrow clearance portion, and after drying, a lubricating coating and a rust-preventing coating can be formed.

  EXAMPLES Hereinafter, although this invention is demonstrated in detail based on an Example and a comparative example, this invention is not limited to this example.

(Preparation of lubricant composition)
Lubricant compositions and lubricating liquid compositions of Examples and Comparative Examples were prepared using the following 3,4,5-trihydroxybenzoic acid compound, lubricating base oil, thickener, amide compound and additives. .
(A) 3,4,5-trihydroxybenzoic acid compound (A1) 3,4,5-trihydroxybenzoic acid propyl (n-propyl) ester (manufactured by Iwate Chemical Co., Ltd.)
(A2) 3,4,5-Trihydroxybenzoic acid octyl (n-octyl) ester (manufactured by Wako Pure Chemical Industries, Ltd.)

(B) Lubricating base oil:
(B1) Polyalphaolefin (PAO, kinematic viscosity (40 ° C.): 400 mm ² / s, viscosity index: 150, pour point: −35 ° C., flash point: 280 ° C.)
(B2) Paraffinic mineral oil (kinematic viscosity (40 ° C.): 32 mm ² / s, viscosity index: 106, pour point: −15 ° C., flash point: 230 ° C.)
(B3) Polyol ester oil (kinematic viscosity (40 ° C.): 10 mm ² / s, viscosity index: 95, pour point: −50 ° C., flash point: 190 ° C.)

(C) Amide compound and thickener:
(C1) Bisamide (ethylenebisstearylbisamide, melting point 150 ° C.)
(C2) Monoamide (N-stearyl stearamide, melting point 95 ° C.)
(C3) Monoamide (N-oleyl oleic acid amide, melting point 35 ° C.)
(C4) Li soap: lithium 12-hydroxystearate (C5) urea compound: aromatic diurea

(D) Additive:
(D1) Oiliness agent: Glycerol monooleate (GMO)
(D2) Molybdenum compound: Molybdenum dithiocarbamate (MoDTC)
(D3) Molybdenum compound: Molybdenum disulfide (MoS ₂ , average particle diameter 1 μm)
(D4) Rust inhibitor: calcium sulfonate

(E) Volatile solvent (E1) Hydrocarbon: normal decane (n-decane)

The lubricant compositions used in the examples and comparative examples were blended as follows using the components A to D described above at the blending ratios shown in Tables 1 and 2 (mass% based on the total amount of the composition). Prepared.
A predetermined amount of the additives (D1) to (D4) is blended in the lubricating base oils (B1) to (B3), and heated and dissolved with a stirring mixer (hot plate stirrer). In Examples 1 to 7, 9 to 10, and Comparative Examples 1 to 3, amide compounds or thickeners of (C1), (C2), and (C4) were added thereto, and the temperature was raised to the melting point or higher. Stir until melted and evenly mixed in liquid state, add 3,4,5-trihydroxybenzoic acid compound of (A1), (A2) and further stir, then let stand to cool to room temperature A uniform semi-solid composition was obtained. In Examples 8 and 11 and Comparative Example 4, the aromatic amine and diisocyanate were heated, dissolved and reacted in the base oil to uniformly disperse the thickener (C5), and a semi-solid lubricant composition at room temperature. I got a thing.

  In Examples 12 to 18 and Comparative Examples 5 to 7, the amide compound (C3) was used, and the mixing ratio shown in Table 3 was used to add a volatile solvent (E1) The mixture was heated and stirred at 40 ° C. for 30 minutes to obtain a lubricating liquid composition.

  For the lubricant compositions and lubricating liquid compositions of Examples 1 to 18 and Comparative Examples 1 to 7 thus obtained, appearance, consistency (immiscible consistency), and lubricating performance (friction coefficient, wear amount) The rust prevention property (black rust conversion effect, rust inhibition property) was measured and evaluated. The obtained measurement and evaluation results are shown in the lower part of Tables 1 to 3.

[Measurement and evaluation method]
The measurement and evaluation were performed by the following method.

〔appearance〕
After blending at a prescribed blending ratio and cooling to room temperature, the finished composition was visually observed. A case where a precipitate or a precipitate was generated and a uniform composition could not be obtained was rejected, and a case where a uniform semi-solid or uniform diluted solution was obtained was recorded as acceptable.

[Consistency]
According to JIS K2220, the immiscible consistency was measured with a ¼ consistency meter.

[Friction test]
The wear resistance was measured using a ball / disk type reciprocating friction tester.
Test conditions are less likely to form an oil film, and in order to simulate severe lubrication conditions, the sliding speed is low (1 cm / s), high load (2200 gf), the test is started at an amplitude of 20 mm and room temperature, and reciprocates for 2 hours. Friction was performed. In addition, the bearing carbon steel (SUJ-2) was used for the test piece of a ball | bowl and a disk. The friction coefficient after 2 hours and the disc wear depth after the test were measured and recorded with a surface roughness meter.

[Rust prevention test]
As a confirmation test of the antirust effect, the lubricating oil composition was applied to artificially created red rust (hematite), and it was measured whether it changed to black rust (magnetite). First, in accordance with JIS K2246, a salt spray test is performed for 3 hours to form red rust on the steel sheet as it is (without applying oil or the like). Subsequently, the lubricating oil composition was sprayed uniformly on the red rust steel plate (1 ml as the spray amount) and left to stand for 24 hours under an atmospheric pressure of 25 ° C., and the appearance of the steel plate was observed. Visually, a case where red rust was converted to black rust by 50% or more was regarded as acceptable, and a case where the conversion rate was 50% or less was recorded as unacceptable. Furthermore, the steel plate 24 hours after application | coating stationary was again subjected to the salt spray test for 24 hours, and the increase degree (inhibition degree) of rusting was evaluated. When the amount of rusting does not change, record the rusting inhibition degree ◎, when it increases 1 to 2 times, the degree of rusting inhibition ○, and when the amount of rusting more than 2 times, rank rusting inhibition degree × did.

The examples shown in Tables 1 and 2 are all in a uniform semi-solid state. In Examples 1 to 11, the consistency is 260 to 285, and the consistency classification corresponds to No. 2. The disk wear depth after the friction test of these examples was 0.05 to 0.14 μm, and the friction coefficient was also stable from 0.05 to 0.09. The low friction characteristic was shown especially by including Mo.
On the other hand, in Comparative Examples 1 to 4 in which no 3,4,5-trihydroxybenzoic acid compound was blended, the wear depth after the test was 0.38 to 0.86 μm, which is deeper than the Examples. The coefficient of friction remained relatively high. Thus, it turns out that abrasion resistance can be improved by mix | blending a 3,4,5- trihydroxybenzoic acid compound with a semi-solid lubricant.

  All the examples shown in Table 3 are uniform dilutions. The wear depth in the friction test of the thin film after the solvent was volatilized was 0.08 to 0.12 μm, and the coefficient of friction was a stable value of 0.06 to 0.09. Furthermore, as a result of the rust prevention test, a conversion effect from red rust to black rust was recognized in the examples, whereas in the comparative examples not containing 3,4,5-trihydroxybenzoic acid compound, the red rust remained unchanged. I did not. Furthermore, as a result of the additional salt spray test, in the examples, no increase in rust was observed, and the effect of suppressing rusting was confirmed. On the other hand, in the comparative example, a significant increase in rust was observed.

  Since the lubricant composition and the lubricating liquid composition of the present invention have high extreme pressure properties, wear resistance and rust prevention properties, various industrial machines such as home appliances, OA equipment, precision machines, machine tools, automobiles, automatic Various types of bearings, gears, belts, chains, wire ropes, hinges, transmission element mechanisms such as mechanical continuously variable transmissions, piston cylinders, drives, etc., widely used in transport machinery and measuring equipment such as motorcycles, bicycles, and railways As a lubricant for various sliding parts such as a system, it can also be used for surface protection of processed materials and machine members.

Claims (9)

  Based on the total amount of lubricant composition of 3,4,5-trihydroxybenzoic acid and / or 3,4,5-trihydroxybenzoic acid ester in mineral base oil, synthetic oil base and / or animal and vegetable base oil A lubricant composition having a semi-solid state at room temperature, in which 0.01 to 20% by mass, and at least one thickener or amide compound is blended in an amount of 1 to 70% by mass based on the total amount of the lubricant composition.   3,4,5-Trihydroxybenzoic acid ester is synthesized with 3,4,5-trihydroxybenzoic acid and a linear or branched alcohol having 3 to 12 carbon atoms. The lubricant composition according to claim 1, wherein the lubricant composition is an alkyl benzoate. The lubricant composition according to claim 1 or 2, wherein the lubricating base oil has a kinematic viscosity at 40 ° C of 5 to 1000 mm ² / s.   The lubricant composition according to any one of claims 1 to 3, which is gel-like at normal temperature in which the amide compound is blended.   The lubricant composition according to any one of claims 1 to 4, which has a consistency of 70 to 480.   The lubricant composition according to any one of claims 1 to 5, wherein the molybdenum compound is contained in an amount of 0.01 to 10% by mass as molybdenum (Mo) based on the total amount of the lubricant composition.   The lubricant composition according to any one of claims 1 to 6, comprising 0.05 to 5.0% by mass of an oily agent based on the total amount of the lubricant composition.   A lubricating liquid composition obtained by mixing 95 to 15 parts by weight of a volatile solvent with respect to 5 to 85 parts by weight of the lubricant composition according to claim 1.   The lubricating liquid composition according to claim 8, wherein the volatile solvent is a hydrocarbon having 6 to 12 carbon atoms.